You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
66 lines
2.3 KiB
Plaintext
66 lines
2.3 KiB
Plaintext
{smcl}
|
|
{* Mars 2012}{...}
|
|
{hline}
|
|
help for {hi:pcmtest}{right:JFH}
|
|
{hline}
|
|
|
|
{title:Global and item specific tests of the fit for Partial Cradit Model}
|
|
|
|
{p 8 14 2}{cmd:pcmtest}, [{cmdab:g:roup}({it:numlist})
|
|
{cmdab:n:fit}(#)
|
|
{cmdab:p:ower}(#)
|
|
{cmdab:graph:ics}(#)
|
|
{cmdab:a:lpha}(#)
|
|
{cmdab:ap:proximation}
|
|
{cmdab:n:ew}]
|
|
|
|
{title:Description}
|
|
|
|
{p 8 14 2}{cmd:pcmtest} allows to test the fit between an observed data and the
|
|
partial credit model.{p_end}
|
|
{p 14 14 2}The global test of the fit (test R1m) can only be computed if the data
|
|
contains at least two items. Item specific test of the fit (Si tests) can only be
|
|
computed if the data contains at least three items. {p_end}
|
|
{p 14 14 2}{cmd:pcmtest} is only performed if item difficulties have been
|
|
estimated using {cmd:pcmodel}. {cmd:pcmtest} can be performed either if covariates
|
|
have been included in {cmd:pcmodel} or not.
|
|
|
|
{title:Options}
|
|
|
|
{p 4 8 2}{cmd:group} specifies groups of scores, by defining the superior limits of
|
|
each group
|
|
|
|
{p 4 8 2}{cmd:nfit} specifies the size of a virtual sample with items response
|
|
distribution strictly identical to that observed ({cmd:nfit} can deal with
|
|
over-power problems when tests of the fit are performed on large samples).
|
|
|
|
{p 4 8 2}{cmd:power} specifies the desired power for a test R1m, and estimates the
|
|
corresponding size of a virtual sample with items response distribution strictly
|
|
identical to that observed.
|
|
|
|
{p 4 8 2}{cmd:alpha} specifies the type I error used to performe the tests of the fit
|
|
(default: 0.05).
|
|
|
|
{p 4 8 2}{cmd:graphics} displays several graphs (Graphical fit between the observed and
|
|
expected latent traits according to the individual scores, graphic of MAP, graphic of
|
|
groups contribution to the R1m statistic, and graphice of the observed and expected
|
|
score distribution)
|
|
|
|
{p 4 8 2}{cmd:approximation} Computation of the pattern response probabilities using
|
|
simulation instead of Gauss Hermitte quadratures. Computation should be quicker for
|
|
high number of items or responses modalities.
|
|
|
|
{p 4 8 2}{cmd:new} Do not use pattern response probabilities computed during a previous
|
|
test of the fit, compute it an other time! (allows changing the computation methodology)
|
|
|
|
{title:Author}
|
|
|
|
{p 4 8 2}Jean-François HAMEL{p_end}
|
|
|
|
{title:Also see}
|
|
|
|
{p 4 13 2}Online: help for {help pcmodel}, {help gllamm}, {help simirt}
|
|
, {help raschtest}.{p_end}
|
|
|
|
|